A landslide caused by typhoon Vicente that buried part of a house in Tuyen Quang Province, on Thursday morning, killing a woman and her two children.

Typhoon Vicente left seven people dead and missing in Vietnam's northern highlands after the storm dwindled to a tropical depression that brought on heavy rains on Wednesday.

Nguyen Thi Thu, 28, and her two children (one 5 years old and the other nearly five months old) were killed in their sleep when a landslide crushed portions of their home in Tuyen Quang Province on Thursday morning, Tuoi Tre reported.

Quang Van Quyen, 8, died after being swept away in a flash flood in Son La Province on Wednesday.

Rescue workers are still looking for three other victims, including a man from Lao Cai and a husband and wife couple in Ha Giang.

A flash flood in Lao Cai swept away Tran Van Truong, 47, at around 5:30 p.m. on Wednesday while he was driving home from his job at an iron mine. The province reported heavy downpours that began on Wednesday afternoon and continued until 10 am Thursday, causing floods along several rivers.

A Leng Van Trieu, 48, and his wife Chao Thi Thao, 55, also remained missing following the heavy rains.

On Monday when the typhoon was still roughly 750 kilometers off Vietnam's northern coast, Prime Minister Hoang Trung Hai said at a meeting that the authorities need to prepare for possible landslides and be "especially careful" about rains after the typhoon.

"Our rain forecasts are not highly accurate yet," he said.

Vicente was the four typhoon from the East Sea to hit Vietnam this year.

The first one, typhoon Pakhar, hit Ho Chi Minh City hard in early April and killed two people in the surrounding provinces. The two subsequent storms, Talim and Doksuri, dissipated in the East Sea in June and caused no casualties in Vietnam.